1// Copyright (c) 2011 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5// This command-line program dumps the contents of a set of cache files, either
6// to stdout or to another set of cache files.
7
8#include <stdio.h>
9#include <string>
10
11#include "base/at_exit.h"
12#include "base/command_line.h"
13#include "base/process_util.h"
14#include "base/string_util.h"
15#include "base/stringprintf.h"
16#include "base/win/scoped_handle.h"
17#include "net/disk_cache/disk_format.h"
18
19enum Errors {
20  GENERIC = -1,
21  ALL_GOOD = 0,
22  INVALID_ARGUMENT = 1,
23  FILE_ACCESS_ERROR,
24  UNKNOWN_VERSION,
25  TOOL_NOT_FOUND,
26};
27
28int GetMajorVersion(const std::wstring& input_path);
29int DumpContents(const std::wstring& input_path);
30int DumpHeaders(const std::wstring& input_path);
31int RunSlave(const std::wstring& input_path, const std::wstring& pipe_number);
32int CopyCache(const std::wstring& output_path, HANDLE pipe, bool copy_to_text);
33HANDLE CreateServer(std::wstring* pipe_number);
34
35const char kUpgradeHelp[] =
36    "\nIn order to use the upgrade function, a version of this tool that\n"
37    "understands the file format of the files to upgrade is needed. For\n"
38    "instance, to upgrade files saved with file format 3.4 to version 5.2,\n"
39    "a version of this program that was compiled with version 3.4 has to be\n"
40    "located beside this executable, and named dump_cache_3.exe, and this\n"
41    "executable should be compiled with version 5.2 being the current one.";
42
43// Folders to read and write cache files.
44const char kInputPath[] = "input";
45const char kOutputPath[] = "output";
46
47// Dumps the file headers to stdout.
48const char kDumpHeaders[] = "dump-headers";
49
50// Dumps all entries to stdout.
51const char kDumpContents[] = "dump-contents";
52
53// Convert the cache to files.
54const char kDumpToFiles[] = "dump-to-files";
55
56// Upgrade an old version to the current one.
57const char kUpgrade[] = "upgrade";
58
59// Internal use:
60const char kSlave[] = "slave";
61const char kPipe[] = "pipe";
62
63int Help() {
64  printf("warning: input files are modified by this tool\n");
65  printf("dump_cache --input=path1 [--output=path2]\n");
66  printf("--dump-headers: display file headers\n");
67  printf("--dump-contents: display all entries\n");
68  printf("--upgrade: copy contents to the output path\n");
69  printf("--dump-to-files: write the contents of the cache to files\n");
70  return INVALID_ARGUMENT;
71}
72
73// Starts a new process, to generate the files.
74int LaunchSlave(const CommandLine& command_line,
75                const std::wstring& pipe_number, int version) {
76  // TODO(port): remove this string-munging hackery.
77  std::wstring hacked_command_line = command_line.command_line_string();
78  const std::wstring old_exe(L"dump_cache");
79  size_t to_remove = hacked_command_line.find(old_exe);
80  hacked_command_line.erase(to_remove, old_exe.size());
81
82  bool do_upgrade = command_line.HasSwitch(kUpgrade);
83  bool do_convert_to_text = command_line.HasSwitch(kDumpToFiles);
84
85  std::wstring new_program;
86  if (do_upgrade)
87    new_program = base::StringPrintf(L"%ls%d", L"dump_cache_", version);
88  else
89    new_program = base::StringPrintf(L"dump_cache");
90
91  hacked_command_line.insert(to_remove, new_program);
92
93  CommandLine new_command_line = CommandLine::FromString(hacked_command_line);
94
95  if (do_upgrade || do_convert_to_text)
96    new_command_line.AppendSwitch(kSlave);
97
98  // TODO(evanm): remove needless usage of wstring from here and elsewhere.
99  new_command_line.AppendSwitchASCII(kPipe, WideToASCII(pipe_number));
100  if (!base::LaunchApp(new_command_line, false, false, NULL)) {
101    printf("Unable to launch the needed version of this tool: %ls\n",
102           new_program.c_str());
103    printf(kUpgradeHelp);
104    return TOOL_NOT_FOUND;
105  }
106  return ALL_GOOD;
107}
108
109// -----------------------------------------------------------------------
110
111int main(int argc, const char* argv[]) {
112  // Setup an AtExitManager so Singleton objects will be destroyed.
113  base::AtExitManager at_exit_manager;
114
115  CommandLine::Init(argc, argv);
116
117  const CommandLine& command_line = *CommandLine::ForCurrentProcess();
118  std::wstring input_path = command_line.GetSwitchValueNative(kInputPath);
119  if (input_path.empty())
120    return Help();
121
122  bool upgrade = false;
123  bool slave_required = false;
124  bool copy_to_text = false;
125  // TODO(evanm): port to FilePath.
126  std::wstring output_path = command_line.GetSwitchValueNative(kOutputPath);
127  // Make sure that output directory ends with a slash.
128  if (output_path.size() >= 1 && output_path[output_path.size() - 1] != '\\')
129    output_path.push_back('\\');
130
131  if (command_line.HasSwitch(kUpgrade))
132    upgrade = true;
133  if (command_line.HasSwitch(kDumpToFiles))
134    copy_to_text = true;
135
136  if (upgrade || copy_to_text) {
137    if (output_path.empty())
138      return Help();
139    slave_required = true;
140  }
141
142  int version = GetMajorVersion(input_path);
143  if (!version)
144    return FILE_ACCESS_ERROR;
145
146  if (version != disk_cache::kCurrentVersion >> 16) {
147    if (command_line.HasSwitch(kSlave)) {
148      printf("Unknown version\n");
149      return UNKNOWN_VERSION;
150    }
151    slave_required = true;
152  }
153
154  std::wstring pipe_number = command_line.GetSwitchValueNative(kPipe);
155  if (command_line.HasSwitch(kSlave) && slave_required)
156    return RunSlave(input_path, pipe_number);
157
158  base::win::ScopedHandle server;
159  if (slave_required) {
160    server.Set(CreateServer(&pipe_number));
161    if (!server.IsValid()) {
162      printf("Unable to create the server pipe\n");
163      return -1;
164    }
165
166    int ret = LaunchSlave(command_line, pipe_number, version);
167    if (ret)
168      return ret;
169  }
170
171  if (upgrade || copy_to_text)
172    return CopyCache(output_path, server, copy_to_text);
173
174  if (slave_required) {
175    // Wait until the slave starts dumping data before we quit. Lazy "fix" for a
176    // console quirk.
177    Sleep(500);
178    return ALL_GOOD;
179  }
180
181  if (command_line.HasSwitch(kDumpContents))
182    return DumpContents(input_path);
183  if (command_line.HasSwitch(kDumpHeaders))
184    return DumpHeaders(input_path);
185  return Help();
186}
187